• Steel and Composite Structures
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• v.5 no.1
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• pp.35-47
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• 2005

This paper presents the results of a series of tests carried out on hollow and concrete-filled coldformed steel sections subjected to axial and bending forces. The effects of eccentricity ratio and strength of in-fill on the behaviour of these sections were studied. A total of forty-eight medium sized columns and six beams were tested to failure. Extensive measurements of material properties, strains, axial shortening and lateral deflection were carried out. Interaction of local and overall buckling was observed in the tests. Failure mode observations were local buckling coupled with overall buckling. A description of the specially fabricated end fixtures for applying eccentric loading to the columns and to simulate pinned end condition is also presented. The experimental results of hollow columns are compared with the existing Indian, British and American codes of practice and the results of concrete-filled columns are compared with EC4 recommendations. It is seen that in the case of hollow columns predictions based on British and American codes of practice and in the case of concrete-filled columns predictions based on EC4 recommendations agree reasonably well with the experimental results. From the experiments it is seen that the provision of in-fill substantially increases the ultimate load carrying capacity of the order of one and a half to two times and the increase in strength of the in-filled concrete from a low grade concrete of compressive strength 24.94 MPa to a high grade concrete of compressive strength 33.26 MPa increases the ultimate load carrying capacity by one and a half times irrespective of the eccentricity of loading.

• Journal of the Korea Society for Simulation
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• v.16 no.2
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• pp.1-8
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• 2007

Resource management in grid computing environment is essential for integration and interaction among heterogeneous resources. This paper discusses resource management methods of centralized and decentralized broker-based modeling for solving complex problems of resource management and presents design and development of the decentralized broker-based resource management modeling in grid computing environment. This model comprises a global resource broker and a local resource broker, and we derive reduction of communication and functional dispersion of Job management using a local resource broker. The simulation experiment shows the improvement of resource utilization and average response time and proves that this model improves utilization of resources and replies to user requests promptly.

• The Journal of Korean Physical Therapy
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• v.15 no.4
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• pp.412-430
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• 2003

Functional stability is dependent on integrated local and global muscle function. Movement dysfunction can present as a local and global problem, though both frequently occur together. To good understand how movement induces pain syndrome, the optimal actions and interaction of the multiple anatomic and functional systems involved in motion must be considered. Minor alterations in the precision of movement cause microtrauma and, if allowed to continue, will cause macrotrauma and pain. These alteration of the movement result in the development of compensatory movement and movement impairment. Muscle that become tight tend to pull the body segment to which they are attached, creating postural deviation. The antagonistic muscles may become weak and allow postural deviations due to lack of balanced support. Both hypertonic and inhibited muscles will cause an alteration of the distribution of pressure over the joint(s) that they cross and, thus, may not only result from muscle dysfunction, but produce joint dysfunction as well. Alteration of the shoulder posture and movement dysfunction may sometimes result in compression of neurovascular structures in the shoulder and arm. There is a clear link between reduced proprioceptive input, altered motor unit recruitment and the neurovascular compression. This report start with understanding of the impaired alignment, movement patterns and neuromuscular compression of the shoulder girdle by movement impairment to approach method of the movement dysfunction.

• Journal of the Korean Society for Precision Engineering
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• v.29 no.6
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• pp.607-612
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• 2012

The wear problem of wheel flange occurs at sharp curves of rail. This paper proposes a procedure for optimum design of a wheel profile wherein flange wear is reduced by improving an interaction between wheel and rail. Application of optimization method to design problem mainly depends on characteristics of design space. This paper compared local optimization method with global optimization according to sensitivity value of objective function for design variables to find out which optimization method is appropriable to minimize wear of wheel flange. Wheel profile is created by a piecewise cubic Hermite interpolating polynomial and dynamic performances are analyzed by a railway dynamic analysis program, VAMPIRE. From the optimization results, it is verified that the global optimization method such as genetic algorithm is more suitable to wheel profile optimization than the local optimization of SQP (Sequential Quadratic Programming) in case of considering the lack of empirical knowledge for initial design value.

• KSII Transactions on Internet and Information Systems (TIIS)
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• v.4 no.2
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• pp.138-153
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• 2010

The interactions between people who do not know each other have been greatly increased with the on-going increase of people's cyberspace activities. In this situation, there exist potential risk factors such as the possibility of fraud, so we need a method to reduce or eliminate those risk factors. Concerning this necessity, rating systems are widely used, and many trust metrics calculated from rate values that people give to each other are proposed to help them make decisions. However, the trust metrics decrease the accuracy, and this is caused by the different rating scales and ranges of each person. So, we propose a fuzzy adjustment method to solve this problem. It is possible to catch the exact meaning of the trust value that each person selects through applying fuzzy sets, which improve the accuracy of the trust metric calculated from the trust values. We have applied our fuzzy adjustment method to the TidalTrust algorithm, a representative algorithm for calculating the local scalar trust metric, and we performed an experimental evaluation with four data sets and three evaluation methods.

• KIEAE Journal
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• v.16 no.2
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• pp.67-77
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• 2016

Purpose: The purpose of this study is to suggest a implication and improvement which can provide direction when proposing prospective housing policies which comply the peculiar and changing needs of rural communities. Method: Accordingly this study reviewed for rural housing regulations and policies that appear in the process of developing Japanese Excellent Rural Housing. According to the case study, municipal organizations have implemented independent housing programs base on the Promotion of Rural Residence Act for returning farmers. Result: They provide service to provide returning farmers comprehensive counseling and information about employment, child-rearing and education, housing, and etc. The service program is run by a cooperative way. In addition the Japanese Excellent Rural Housing projects nowadays focus on promoting voluntary establishments of local communities by providing comprehensive plans for local community formation and interaction for harmony between existing residents and returning farmers. In the case of Korea, targeting existing residents and returning farmers for settlement environment in rural areas need jobs, child care, education, and comprehensive housing counseling. In addition, this suggests the need for linkages between the various community programs and residents.

• Steel and Composite Structures
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• v.19 no.5
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• pp.1299-1319
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• 2015

This paper presents a detailed parametric study, conducted using finite element tools to cover a range of several geometric and material parameters, on the behaviour of thin-walled partially encased composite (PEC) columns. The PEC columns studied herein are composed of thin-walled built-up H-shaped steel sections with concrete infill cast between the flanges. Transverse links are provided between the opposing flanges to improve resistance to local buckling. The parametric study is confined to eccentrically-loaded columns subjected to major axis bending only. The parameters that were varied include the overall column slenderness ratio (L/d), load eccentricity ratio (e/d), link spacing-to-depth ratio (s/d), flange plate slenderness ratio (b/t) and concrete compressive strength ($f_{cu}$). The overall column slenderness ratio was chosen to be the primary variable with values of 5, 10 and 15. Other parameters were varied within each case of L/d ratio. The effects of the selected parameters on the behaviour of PEC columns were studied with respect to the failure mode, peak axial load, axial load versus average axial strain response, axial load versus lateral displacement response, moment versus lateral displacement behaviour and the axial load-moment interaction diagram. The results of the parametric study are presented in the paper and the influences of each of the parameters investigated are discussed.

• International Journal of Naval Architecture and Ocean Engineering
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• v.6 no.4
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• pp.1024-1040
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• 2014

The theoretical background and a numerical solution procedure for a time domain hydroelastic code are presented in this paper. The code combines a VOF-based free surface flow solver with a flexible body motion solver where the body linear elastic deformation is described by a modal superposition of dry mode shapes expressed in a local floating frame of reference. These mode shapes can be obtained from any finite element code. The floating frame undergoes a pseudo rigid-body motion which allows for a large rigid body translation and rotation and fully preserves the coupling with the local structural deformation. The formulation relies on the ability of the flow solver to provide the total fluid action on the body including e.g. the viscous forces, hydrostatic and hydrodynamic forces, slamming forces and the fluid damping. A numerical simulation of a flexible barge is provided and compared to experiments to show that the VOF-based flow solver has this ability and the code has the potential to predict the global hydroelastic responses accurately.

• Asian Journal of Turfgrass Science
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• v.12 no.1
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• pp.1-16
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• 1998

Vegetation of golf courses and local difference of feeding host plants of brown chafer, Adoretus tenuimaculatus Waterhouse(Coleoptera: Scarabaeidae) were investigated in golf courses. Yongwon country club in Chinhae and Tongdo country club in Yangsan Gyeongnarn, Dongrae Benest golf club in Kumjeunggu Pusan and Daegu country club in Gyeongsan Gyeongbuk province from 1995 to 1997. Vegetation and species of feeding host plant were different depending on observed place. Damaged rate of host plants were concerned with ornamental trees and natural growing host plants, and Oenothera odorata, Achyranthes japonica, Aralia elata, Viburnum awabuki, Chenapadium album var. cent rorubrum, Cornus officinalis, and Rhododendron mucronulatum were newly recorded as host plant of A. tenuimaculatus in this study. Thus, host plants of A. tenuimaculatus were 193 kinds in 48 families. Key words: Brown chafer, Adoretus tenuimaculatus, host plant, vegetation, insect-plant interaction, biological control, golf courses.

• Steel and Composite Structures
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• v.28 no.2
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• pp.251-266
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• 2018

Compared to conventional flat web I-beams, the prediction of shear buckling stress of corrugated web steel beams (CWSBs) is not straightforward. But the CWSBs combined advantages of lightweight large spans with low-depth high load-bearing capacities justify dealing with such difficulties. This work investigates experimentally and analytically the shear strength of trapezoidal CWSBs. A set of large scale CWSBs are manufactured and tested to failure in shear. The results are compared with widely accepted CWSBs shear strength prediction models. Confirmed by the experimental results, the linear buckling analyses of trapezoidal corrugated webs demonstrated that the local shear buckling occurs only in the flat plane folds of the web, while the global shear buckling occurs over multiple folds of the web. New analytical prediction model accounting for the interaction between the local and global shear buckling of CWSBs is proposed. Experimental results from the current work and previous studies are compared with the proposed analytical prediction model. The predictions of the proposed model are significantly better than all other studied models. In light of the dispersion of test data, accuracy, consistency, and economical aspects of the prediction models, the authors recommend their proposed model for the design of CWSBs over the rest of the models.